Cannot cancel debit order

I canceled my contract with herotel a few months after the one year contract expired. Herotel is still deducting debit orders. Reversing these debit orders cost me money. You are waiting my money by trying to ***** my money. I had a contract, I fulfilled my side of the contract, and I canceled without any problems or requests for further payment, but you still take my money. For you it seems it's clearly a lifetime contract. Please do not take more money from me, I'm finished with you. I will never make use of your services again. Just to difficult to safeguard my money from you.